Systems and methods for enhanced user equipment assistance information in wireless communication systems

ABSTRACT

Systems and methods are disclosed for communicating enhanced user equipment (UE) assistance information between nodes in wireless communication systems. The UE achieves power savings and latency requirements more effectively by communicating its preferences, constraints and/or requirements to an evolved Node B (eNodeB) in the form of UE assistance information. The UE assistance information may include, for example, an indication of a preferred set of discontinuous reception (DRX) settings, current data traffic conditions, expected data traffic conditions, power or performance preferences, and/or an indication of the UE&#39;s mobility between cells.

RELATED APPLICATION

This application claims the benefit under 35 U.S.C. § 119(e) of U.S.Provisional Application No. 61/646,223, filed May 11, 2012, which ishereby incorporated by reference herein in its entirety.

TECHNICAL FIELD

This disclosure relates to wireless communication networks.Specifically, this disclosure relates to systems and methods forcommunicating enhanced user equipment assistance information betweennodes in wireless communication systems.

BACKGROUND

Wireless mobile communication technology uses various standards andprotocols to transmit data between a base station and a wireless mobiledevice. Wireless communication system standards and protocols caninclude the third generation partnership project (3GPP) long termevolution (LTE), the Institute of Electrical and Electronics Engineers(IEEE) 802.16 standard, which is commonly known to industry groups asWiMAX (Worldwide interoperability for Microwave Access), and the IEEE802.11 standard, which is commonly known to industry groups as WiFi. In3GPP radio access networks (RANs) in LTE systems, the base station canbe a combination of Evolved Universal Terrestrial Radio Access Network(E-UTRAN) Node Bs (also commonly denoted as evolved Node Bs, enhancedNode Bs, eNodeBs, or eNBs) and Radio Network Controllers (RNCs) in anE-UTRAN, which communicates with the wireless mobile device, known as auser equipment (UE). A downlink (DL) transmission can be a communicationfrom the base station (or eNodeB) to the wireless mobile device (or UE),and an uplink (UL) transmission can be a communication from the wirelessmobile device to the base station.

In many wireless systems, including previous LTE systems, UEs havelittle or no control over certain functions and processes that prolongthe UE's battery and/or achieve better performance (e.g., in terms oflatency) for applications running on the UE. Rather, many such functionsand processes are determined by the eNodeB without input from the UE.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of a UE communicating UE assistanceinformation to an eNodeB according to one embodiment.

FIGS. 2A and 2B illustrate respective data structures of the UEassistance information with traffic type information according tocertain embodiments.

FIG. 3A illustrates a data structure of the UE assistance informationwith a type identifier and one or more inter-arrival time valuesaccording to one embodiment.

FIG. 3B illustrates example descriptions of the type identifier shown inFIG. 3A for different traffic types according to one embodiment.

FIG. 4 is a flow chart for selectively reporting packet inter-arrivaltime or next packet arrival information according to one embodiment.

FIG. 5A illustrates a data structure of the UE assistance informationwith a toggle bit according to one embodiment.

FIG. 5B illustrates example descriptions of the toggle bit shown in FIG.5A according to certain embodiments.

FIG. 6 illustrates a data structure of the UE assistance informationincluding a mobility state indicator bit according to one embodiment.

FIG. 7 illustrates a data structure of the UE assistance informationincluding a traffic type bit according to one embodiment.

FIG. 8 illustrates a data structure of the UE assistance informationincluding a power preference bit according to one embodiment.

FIG. 9 illustrates communication of UE assistance information between aUE and an eNodeB according to certain example embodiments.

FIG. 10 is a flow chart of a method for selecting or modifying a set ofdiscontinuous reception parameters according to one embodiment.

FIG. 11 provides an example illustration of the mobile device that maybe used with one or more of the embodiments disclosed herein.

DETAILED DESCRIPTION

A detailed description of systems and methods consistent withembodiments of the present disclosure is provided below. While severalembodiments are described, it should be understood that disclosure isnot limited to any one embodiment, but instead encompasses numerousalternatives, modifications, and equivalents. In addition, whilenumerous specific details are set forth in the following description inorder to provide a thorough understanding of the embodiments disclosedherein, some embodiments can be practiced without some or all of thesedetails. Moreover, for the purpose of clarity, certain technicalmaterial that is known in the related art has not been described indetail in order to avoid unnecessarily obscuring the disclosure.

As discussed above, UEs have little or no control over certain functionsand processes that prolong the UE's battery and/or minimize latency forapplications running on the UE. For example, a base station, such as aneNodeB, controls the RAN functions to support the UE. However, due tothe proliferation of smartphones and other mobile devices that rundiverse mobile internet applications, the UE can achieve power savingsand latency requirements more effectively if it is allowed tocommunicate its preferences, constraints and/or requirements to theeNodeB in the form of UE assistance information.

FIG. 1 illustrates an example of a UE 100 communicating UE assistanceinformation 112 to an eNodeB 114 according to one embodiment. The UE 100includes a transceiver module 116 and a processing module 118. Theprocessing module 118 is configured to generate the UE assistanceinformation 112 and perform other functions of the UE 100 as describedherein. The transceiver module 116 is configured to transmit the UEassistance information 112 to the eNodeB 114 and to transmit and receiveother signals and messages as described herein. The eNodeB 114 includesa transceiver module 120 and a processing module 122. The transceivermodule 120 is configured to receive the UE assistance information 112from the UE 100 and to transmit and receive other signals and messagesas described herein. The processing module 122 is configured to processthe UE assistance information 112 received from the UE 100 and toperform other functions described herein.

The eNodeB 114 can use the UE assistance information 112 to adoptcertain RAN functions and parameters to enhance the UE's and network'sperformance. For example, the UE assistance information 112 may beuseful to the eNodeB 114 in selecting optimal discontinuous reception(DRX) settings in order to achieve improved power savings at the UE 100.

Certain embodiments disclosed herein provide enhancements to the UEassistance information 112 that enable the eNodeB 114 to adjust the DRXparameters per UE 100 based on UE indications (e.g., the packet interarrival time and/or traffic type characteristics) to achieve desiredperformance requirements and/or to save power. For example, the UEassistance information 112 according to certain embodiments may includea packet inter-arrival time (IAT), a mobility state indicator (MSI), adata and/or traffic type characteristic, a timer alignment timer (TAT)feedback value, and combinations of the foregoing. Each of thesedifferent types of UE assistance information 112 is discussed in detailbelow. Skilled persons will recognize from the disclosure herein thatother embodiments may use UE assistance information 112 havingadditional or different elements such as other DRX parameters orparameter sets, battery constraint indicators, quality of experience(QoE) metrics, and/or a request to go to idle mode. After discussing theexamples of UE assistance information, examples for signaling the UEassistance information an example UE are provided.

I. Examples of UE Assistance Information

A. Packet IAT

In one embodiment, the UE assistance information 112 includes dataassociated with UL packet IAT at the UE 100. The packet IAT is ameasurement of the time period between packet arrivals at the UE 100 andmay correspond to the types of applications currently running on the UE100. The UE 100 may measure the packet IAT, but the eNodeB 114 does notknow the packet IAT of the UL packets at the UE 100. It is possible forthe eNodeB 114 to guess the UL packet IAT at the UE 100 by processingthe UL packets at the eNodeB 114. However, such estimations by theeNodeB 114 are generally not accurate because the packet IAT of thepackets seen by the eNodeB 114 may be altered based on the grants thatthe eNodeB's UL scheduler provides to the various UEs within a cell.Thus, certain embodiments provide the UE assistance information 112 fromthe UE 100 to the eNodeB 114 including data associated with packetarrival.

It may be useful for the eNodeB 114 to know the types of applicationscurrently running on the UE 100. For example, if the UE 100 determines along packet IAT, the eNodeB 114 may put the UE 100 into idle mode or seta longer DRX cycle length to save power. If, however, the UE 100measures a short packet IAT, the eNodeB 114 may set a shorter DRX cyclelength.

Embodiments discussed below include using a single bit of packet IAT UEassistance information, using multiple bits of packet IAT UE assistanceinformation, selectively reporting different formats of packet IAT, andselectively reporting packet IAT information or next packet arrivalinformation.

A(1)—Single Bit Traffic Type or Packet IAT UE Assistance Information

In certain embodiments, the UE 100 is configured to communicate traffictype characteristics. The traffic type may relate to the packet IAT orother factors such whether an application is active or running in thebackground, or whether the screen saver of the UE is active because theuser has not been interacting with the device. Thus, packet IAT is oneof several ways available to the UE to determine whether UL traffic isbackground traffic or active traffic. For example, the UE 100 mayperform packet IAT measurements for use in internal calculations orprocessing. If the measured packet IAT is relatively short (e.g., one ortwo seconds or less), then the UE 100 may determine that the UL trafficis active traffic. If, however, the measured packet IAT is relativelylong (e.g., multiple seconds, tens of seconds, or minutes), then the UE100 may determine that the UL traffic is background traffic. Inaddition, or in other embodiments, the UE 100 may know that currenttraffic is background traffic because there is not any active or openapplication running on the UE 100.

FIG. 2A illustrates a data structure of the UE assistance information112 with a single bit 210 of traffic type information according to oneembodiment. In this example, the UE 100 sets the bit 210 to “0” toindicate that the current traffic is background traffic, and the UE 100sets the bit 210 to “1” to indicate that the current traffic is activetraffic.

A(2)—Multiple Bit Traffic Type or Packet IAT UE Assistance Information

In another embodiment, the UE 100 is configured to communicate traffictype information (e.g., determined using the packet IAT information oranother method) to the eNodeB 114 using a plurality of bits of UEassistance information 112. Thus, the UE 100 may provide the traffictype with different levels of granularity, depending on the number ofbits used.

FIG. 2B illustrates a data structure of the UE assistance information112 with two bits 212 of traffic type information according to oneembodiment. In this example, the UE 100 sets the bits 212 to “00” toindicate a type of application with background traffic where the packetIAT is sparse and farther apart. Thus, the application has lowapplication performance requirements (e.g., in terms of latency, jitter,and other parameters). The UE 100 sets the bits 212 to “01” to indicatethat one or more applications are running that require mediumperformance priority traffic. This type of traffic may not be veryperiodic such as for hypertext transfer protocol (HTTP) web browsing ordownloading. The UE 100 sets the bits 212 to “10” to indicate a type ofapplication with active traffic with a high priority and tight latencyand/or performance requirements. Examples of applications with veryactive traffic requirements include voice over internet protocol (VoIP)or online gaming applications. The UE 100 sets the bits 212 to “11” toindicate that traffic is not expected, which may be interpreted as aradio resource control (RRC) release indicator from the UE 100 to theeNodeB 114.

In other embodiments, the UE assistance information 112 may use three ormore bits to increase the granularity of the traffic type information orthe packet IAT information. For example, a plurality of bits may be usedto communicate the actual packet IAT time (e.g., 10 seconds).

A(3)—Selectively Reporting Different Packet IAT Formats

In certain embodiments, the UE 100 is configured to selectivelycommunicate packet IAT information using different formats orstatistical representations. The selection may be based on, for example,the current type of traffic. Packet IAT may be different for eachpacket. Rather than sending a different packet IAT for each packet, someembodiments may represent more than one packet using a statistical formof the packet IATs over a particular period or for a specified event.For example, the packet IAT may be represented as a minimum IAT and amaximum IAT. As another example, the packet IAT may be represented by amean IAT and a maximum IAT (e.g., with an understanding that the minimumIAT can be zero).

For certain applications, the traffic is bursty and/or infrequent. Forexample, a plurality or burst of packets may be transmitted everyseveral seconds or so. An average IAT or mean IAT for bursty packettraffic does not provide sufficient information because it does notindicate how the packets arrive. A packet IAT for the duration of theburst of packets is referred to herein as a “short IAT” and a packet IATfor the duration between two consecutive bursts is referred to herein asa “long IAT.” The short IAT may be very small, e.g., on the order of oneor a few milliseconds. The long IAT may be very large, e.g., on theorder of one or more seconds. In one embodiment, the UE 100 reports boththe short IAT and the long IAT to the eNodeB 114 to accurately describebursty traffic. The UE 100 may report average values of the short IATand/or the long IAT.

FIG. 3A illustrates a data structure of the UE assistance information112 with a type identifier (ID) 310 and one or more IAT values 312according to one embodiment. The UE 100 knows the type of traffic andthe format used to communicate the one or more IAT values 312 to theeNodeB 114. In order for the eNodeB 114 to correctly interpret the oneor more IAT values 312, the type ID 310 specifies the format. FIG. 3Billustrates example descriptions 314 of the type ID 310 shown in FIG. 3Afor different traffic types 316 according to one embodiment. As shown inFIG. 3B, the type ID 310 includes two bits. However, other embodimentsmay use a single bit or more than two bits. In this example, the UE 100sets the type ID 310 to “00” when the traffic is bursty and/orinfrequent to indicate that the reported IAT values 312 include averageshort and long IATs. For regular (e.g., not bursty) traffic, the UE 100sets the type ID 310 to “01” to indicate that the reported IAT values312 include minimum and maximum IATs, to “10” to indicate that thereported IAT values 312 include mean and maximum IATs, and to “11” toindicate that the reported IAT values 312 include other predetermined(e.g., known to both the UE 100 and the eNodeB 114) formats, which mayinclude other statistical representations of the IAT over apredetermined period or for a predetermined event.

A(4)—Selectively Reporting IAT Vs. Next Packet Arrival Information

In certain embodiments, the UE 100 may selectively report next packetarrival information rather than a packet IAT value (e.g., average IAT ormaximum IAT). The next packet arrival information may be a prediction bythe UE 100 or may be based on information passed from an application viaan application programming interface (API) to the device/media accesscontrol (MAC) layer. In some cases, information about very next packetarrival time can be more beneficial than the average or max IAT.

As discussed above, the packet IAT is a measure of the interval betweentwo successively arriving packets or bursts or packets. The packet IATis useful, for example, to decide if the current DRX configuration ofthe connected mode is appropriate or should it be adjusted. The nextpacket arrival time, on the other hand, corresponds to the intervalbetween a current uplink transmission and a next arriving packet. Thenext packet arrival time is useful, for example, to decide if the UE 100should be put in idle mode when no packets are expected in the nearfuture, or whether the UE 100 should be kept in the connected mode whenpackets are expected soon.

FIG. 4 is a flow chart for selectively reporting packet IAT or nextpacket arrival information according to one embodiment. In this example,the UE 100 queries 400 whether there are more packets in its UL transmitbuffer. If there are no more packets in the UL transmit buffer, the UE100 sends 410 the next packet arrival time so that the eNodeB 114 candecide whether the UE 100 should be put in idle mode or kept inconnected mode. If, however, there are packets still in the UL transmitbuffer, the UE 100 sends 412 the packet IAT information (e.g., asdescribed above) so that the eNodeB can perform RAN functionalityoptimization such as deciding whether the DRX configuration of theconnected mode is appropriate or whether the DRX configuration should beadjusted.

Some UEs may not have the capability to determine the packet IAT and/orto predict the next packet arrival time. Thus, in certain embodiments,the UE 100 is configured to indicate its capability of determining thepacket IAT and predicting the next packet arrival time to eNodeB 114(e.g., when establishing a connection with the eNodeB 114). Thiscapability information may be communicated, for example, using a featuregroup indicator (FGI) bit. For example, one of the currently undefinedFGI bits (bit numbers 37 to 64) such as bit number 38 can be used.

FIG. 5A illustrates a data structure of the UE assistance information112 with a toggle bit 510 for indicating whether an arrival time value512 corresponds to packet IAT or next packet arrival time valuesaccording to one embodiment. The UE assistance information 112 in FIG.5A may, for example, be communicated via a MAC control element (CE) thatcan be appended to the MAC protocol data unit (PDU). In one embodiment,one of the logical control identification (LCD) values (e.g.,01011-11000) for the uplink shared channel (UL-SCH) is used for the MACCE. In this example, five bits are used to represent the arrival timevalue 512 and the remaining bits may be reserved for future use, asshown. In other embodiments, less than five bits or more than five bitsmay be used to represent the arrival time value 512.

As discussed below, other types of messages (e.g., RRC messages) mayalso be used to communicate the arrival time values and other types ofUE assistance information. For example, UE specific IAT or next packetarrival information may be sent to the eNodeB 114 by including theinformation in one of the information elements (IEs) of the uplinkdedicated control channel (UL-DCCH) messages. In one embodiment, an IEcalled “UE-IAT-NextPacketArrival” includes the IAT or next packetarrival information and may be included in the UEInformationResponsemessage used by the UE 100 to transfer information requested by theeNodeB 114. An example UE-IAT-NextPacketArrival message structure isshown below, which includes the options of short, long, and regularIATs:

UE-IAT-NextPacketArrival-r11 ::= SEQUENCE { ue-IAT-NextPacketArrival-typeid BIT STRING (SIZE (2)), ue-IAT-NextPacketArrival-Report  CHOICE { ue-IAT-NextPacketArrival-ShortLong  UE-IAT-NextPacketArrival-ShortLong, ue-IAT-NextPacketArrival-Regular  UE-IAT-NextPacketArrival-Regular  } }UE-IAT_NextPacketArrival-ShortLong ::= CHOICE { next-packet-arrival-shortLong  SEQUENCE {  short-NPA-mean   BIT STRING(SIZE (3.N)),  long-NPA-mean   BIT STRING (SIZE (3..N))   }, ue-IAT-shortLong  SEQUENCE {  short-IAT-mean   BIT STRING (SIZE(3..N)),  long-IAT-mean }   BIT STRING (SIZE (3..N))   }UE-IAT-NextPacketArrival-Regular ::=  CHOICE { next-packet-arrival-regular   SEQUENCE {  min-mean-NPA    CHOICE { min-NPA     BIT STRING (SIZE (3..N)),  mean-NPA     BIT STRING (SIZE(3..N))   },  Max-NPA },    BIT STRING (SIZE (3..N))  },  ue-IAT-regular SEQUENCE {  min-mean-IAT   CHOICE {  min-IAT     BIT STRING (SIZE(3..N)),  mean-IAT     BIT STRING (SIZE (3..N))   },  Max-IAT   BITSTRING (SIZE (3..N))  } }

FIG. 5B illustrates example descriptions 514 of the toggle bit 510 andarrival time value 512 shown in FIG. 5A according to certainembodiments. In this example, the UE 100 sets the toggle bit 510 to “0”to indicate that the arrival time value 512 includes packet IATinformation and to “1” to indicate that the arrival time value 512includes next packet arrival time information. As shown in FIG. 5B, thebits of the arrival time value 512 in one embodiment represent anabsolute time value and in another embodiment represent an index value.The absolute time value may indicate, for example, 1 millisecond, 10milliseconds, 100 milliseconds, 1 second, 10 seconds, or any other timevalue. Alternatively, the index value may correspond to a range of timevalues. With five bits, for example, the possible indexes range from“00000” to “11111.” The indexes may be mapped to actual IAT values orvalue ranges. For example, an index of “00000” may be mapped to a rangeof 1 millisecond to 100 milliseconds, an index of “00001” may be mappedto a range of 101 milliseconds to 200 milliseconds, and so on.

B. Mobility State Indicator (MSI)

In one embodiment, the UE assistance information 112 includes an MSI ofthe UE 100. When the UE 100 is traveling between cells, the overhead orresources required for handover from a first eNodeB to a second eNodeBis greater if the UE 100 is in active mode than it is if the UE 100 isin idle mode. When the UE 100 is in the active mode, the first eNodeBcommunicates the information necessary for the handover to the secondeNodeB. When the UE 100 is in idle mode, however, the informationnecessary for handover is not in the first eNodeB. Rather, theinformation in the idle mode is in a mobility management entity (MSE) ofthe evolved packet core. Thus, for example, communicating the MSI fromto UE 100 to the eNodeB 114 reduces signaling overhead and systemresources by allowing the eNodeB 114 to release the RRC connection andmove the UE 100 to an RRC idle state when it is moving at high speed.

FIG. 6 illustrates a data structure of the UE assistance information 112including an MSI bit 610 according to one embodiment. In this example,the UE 100 sets the MSI bit 610 to “0” to indicate that the UE 100 haslow mobility or no mobility, and the UE 100 sets the MSI bit 610 to “1”to indicate that the UE 100 has high mobility. Skilled persons willrecognize from the disclosure herein that additional bits may be usedfor increased granularity (e.g., to indicate a high mobility state, amedium mobility state, a normal mobility state, and a low or no mobilitystate).

In one embodiment, the MSI bit 610 is preconfigured via signalingthrough open mobile alliance device management (OMA-DM) or an operator(e.g., for fixed-location or machine type communication (MTC) onlydevices). In another embodiment, the MSI bit 610 is updated based onsignaling from a global navigation satellite system (GNSS) or othernavigation system. In another embodiment, the MSI bit 610 is updatedthrough MSE and the number of cell reselections or handovers performedduring a predetermined period of time. For example, in an RRC idlestate, the tracking may be done based on counting the number of cellreselections in a selected period. Whereas, in an RRC connected state,the tracking may be done based on counting the number of handovers in aselected period. Skilled persons will understand that one or multiplesolutions can be used to identify the mobility state of the UE 100. Themapping of the mobility status information available in the UE 100 tothe indicator (e.g., the MSI bit in FIG. 6) and transporting the MSI bit610 as part of the UE assistance information 112 to the eNodeB 114 helpsthe eNodeB 114 to make faster and more accurate UE settings decisions,which in turn helps the UE 100 to save battery life.

C. Data and/or Traffic Type Characteristics

In one embodiment, the UE assistance information 112 includes data typecharacteristics and/or traffic type characteristic. An example oftraffic type is the background or active traffic discussed above withrespect to FIGS. 2A and 2B. As another example, the UE assistanceinformation 112 may include an indication of whether traffic is mobileoriginated (MO) type traffic or mobile terminated (MT) type of traffic.MO and MT type traffic refers to whether the traffic is expected to beUL only, DL only, both UL and DL type traffic. FIG. 7 illustrates a datastructure of the UE assistance information 112 including a traffic typebit 710 according to one embodiment. In this example, the UE 100 setsthe traffic type bit 710 to “0” to indicate that the traffic is ULtriggered data (e.g., a social networking application uploading textand/or photos), and the UE 100 sets the traffic type bit 710 to “1” toindicate that the traffic is DL triggered data (e.g., a web browserapplication downloading a web page). The eNodeB 114 may use the traffictype information to adjust its UL allocations and/or the DRX cyclesbased on the expected periodicity of the indicated traffic type.

In one embodiment, the data and/or traffic type may be in the form of apower preference indication. For example, the UE 100 may communicate apreference for normal power settings when processing active traffic anda preference for reduced or low power settings when processingbackground traffic. FIG. 8 illustrates a data structure of the UEassistance information 112 including a power preference bit 810according to one embodiment. In this example, the UE 100 sets the powerpreference bit 810 to “0” to indicate a preference for normal powersettings (e.g., in active mode) and the UE 100 sets the power preferencebit 810 to “1” to indicate a preference for low power settings (e.g., inbackground mode). Based on the power preference bit 810, the eNodeB 114can selectively adjust the UE's DRX configuration settings and otherparameters. When the power preference bit 810 is set for low powersettings (e.g., optimized power savings), for example, the eNodeB 114may select a long DRX cycle or RRC connection release.

D. Time Alignment Timer (TAT) Feedback

In one embodiment, the UE assistance information 112 includes TATfeedback indicating a particular or desired value for the TAT. In LTEsystems, the eNodeB 114 configures the TAT for each UE. The UEs usetheir TAT timers to maintain UL time alignment. When the TAT expires fora particular UE, the eNodeB 114 releases the UL control channels forthat UE and the UE cannot provide UL transmissions until it performs aUL time alignment procedure.

In certain embodiments, the UE 100 is configured to provide feedbackusing the TAT timer to indicate to the eNodeB 114 to release its ULcontrol channels. In one such embodiment, the UE 100 provides thefeedback by requesting that the TAT value be set to a minimum value orby requesting another specific value (e.g., as the UE 100 might stayconnected for a longer time but does not want to waste UL resource). Inaddition, or in other embodiments, the UE 100 may request that the TATbe set to a very high value to prevent the timer from expiring for alonger time such as during a longer DRX sleep period. A high TAT valuemay be useful, for example, where the UE 100 is expected to have low orno mobility (e.g., for certain MTC devices such as devices like smartmeters or sensors).

II. Example Signaling of UE Assistance Information

The embodiments described below for communicating the UE assistanceinformation from the UE 100 to the eNodeB 114 are provided by way ofexample. Skilled persons will recognize from the disclosure herein thatmany different types of messages, formats, or protocols may be used.

FIG. 9 illustrates communication between a UE 100 and an eNodeB 114 toassign a DRX set based on UE assistance information according to certainexample embodiments. As discussed below, the communications shown inFIG. 9 include the eNodeB 114 sending a list of available DRX sets tothe UE 100 using a MAC-MainConfig information element (IE) 910, the UE100 sending UE assistance information to the eNodeB 114 in aUE-AssistanceInfo IE 912, and the eNodeB 114 sending an assigned DRX set(or index) to the UE 100 in a drxSet-Config IE 914.

The eNodeB 114 sends the list of DRX sets to the UE 100 at connectionestablishment or reestablishment using a RadioResourceConfigDedicated IEto modify the MAC-MainConfig IE 910. The eNodeB 114 may send the list ofDRX sets at any time if, for example, the list changes. In oneembodiment, the MAC-MainConfig IE 910 lists N number of DRX setsavailable at the eNodeB 114. To support multi-DRX switching, multiplesets of DRX sets (<=N) may be used. One or more of the DRX sets may beperformance optimized such as for minimal end-to-end delay. Other DRXsets may, for example, be optimized for power savings. Another type DRXset may provide a balance between performance and power saving.

The MAC-MainConfig IE 910 may include a “drxset-index” parameter thatidentifies a specific DRX set available at the eNodeB 114. Thedrxset-index helps to reduce signaling overhead for multi-DRXembodiments because the eNodeB 114 can send the drxset-index (which maybe a few bits depending on the value of N) rather than all of the DRXparameters related to that particular DRX set. In certain embodiments,however, the eNodeB 114 initially sends a list of all DRX sets availableat the eNodeB 114 to the UE 100. The MAC-MainConfig IE 910 may alsoinclude an “assigned-DrxSetIndex” parameter that indicates to the UE 100the DRX set number to be used for the first time after getting the listof DRX sets.

Referring again to FIG. 9, the UE-AssistanceInfo IE 912 may include, forexample, a preferred DRX set or preferred DRX index, data expected,power or performance preferences, MSI, or other types of UE assistanceinformation (e.g., background/active traffic, other trafficcharacteristics, TAT timer feedback, IAT, and/or next packet arrivaltime, as discussed above). In one embodiment, the UE-AssistanceInfo IE912 sent from the UE 100 to the eNodeB 114 is included in the UL-DCCH.An example UL-DCCH message structure including the UE-AssistanceInfo IE912 is provided as:

-- ASN1START UL-DCCH-Message ::= SEQUENCE { message UL-DCCH-MessageType} UL-DCCH-MessageType ::= CHOICE { c1 CHOICE {  csfbParametersRequestCDMA2000 CSFBParametersRequestCDMA2000,  measurementReport MeasurementReport,  rrcConnectionReconfigurationCompleteRRCConnectionReconfigurationComplete,  rrcConnectionReestablishmentCompleteRRCConnectionReestablishmentComplete,   rrcConnectionSetupCompleteRRCConnectionSetupComplete,   securityModeComplete SecurityModeComplete,  securityModeFailure SecurityModeFailure,   ueCapabilityInformationUECapabilityInformation,   ulHandoverPreparationTransferULHandoverPreparationTransfer,   ulInformationTransferULInformationTransfer,   counterCheckResponse CounterCheckResponse,  ueInformationResponse-r9 UEInformationResponse-r9,  proximityIndication-r9 ProximityIndication-r9,  rnReconfigurationComplete-r10 RNReconfigurationComplete-r10,  mbmsCountingResponse-r10 MBMSCountingResponse-r10,  interFreqRSTDMeasurementIndication-r10InterFreqRSTDMeasurementIndication-r10 }, later CHOICE{  c2 CHOICE{   rrcUEAssistanceMessage RRCUEAssistanceMessage,    spare15 NULL,spare14 NULL, spare13 NULL,    spare12 NULL, spare11 NULL, spare10 NULL,   spare9 NULL, spare8 NULL, spare7 NULL,    spare6 NULL, spare5 NULL,spare4 NULL,    spare3 NULL, spare2 NULL, spare1 NULL  } messageClassExtension SEQUENCE { } } } -- ASN1STOP

In other embodiments, the UE-AssistanceInfo IE 912 is defined as one ofthe noncritical extensions of existing IEs that can be carried by theUL-DCCH messages such as “RRCConnectionReconfigurationComplete,”“RRCConnectionReestablishmentComplete,” “rrcConnectionSetupComplete,”and/or “ueInformationResponse,” as shown in the example UL-DCCH messagestructure above. Such messages are generally sent in response to someeNodeB initiated RRC messages. Thus, the UE may not be able to send UEassistance information exactly when needed because it is waiting for oneof these messages to be triggered. As shown in FIG. 9, certainembodiments of the UE-AssistanceInfo IE 912 include a new ULRRCUEAssistanceMessage for communicating UE assistance informationtransmission triggered by the UE. In such embodiments, the UE can sendthe UE assistance information to the eNodeB at any time.

For example, the RRCConnectionReconfigurationComplete message mayinclude a “data-Expected” field to indicate that indicate that data isexpected to arrive in the near future, a“power-Or-Performance-preferred” field to indicate the characteristicsof a running application in terms a power savings preference or aperformance preference, a “mobility-State-Indication” field to indicatemobility (e.g., in terms of the number of handovers or cell reselectionsper unit time), a “preferred-DrxSet” field to indicate a specific set ofDRX settings requested by the UE 100 to optimize its performance, a“preferred-Drxset-Index” field with an index value corresponding to aDRX set that the UE 100 wants to configure in the future, combinationsof the foregoing, and/or other fields to communicate the UE assistanceinformation disclosed herein.

By way of example, a UE assistance parameter called“powerPreference-Indication” may be used to indicate whether the UE 100supports power preference indication (discussed above) and anRRCConnectionReconfiguration message may include a“powerPrefIndicationConfig” IE that is used to provide informationrelated to the UE's power saving preference. ThepowerPrefIndicationConfig 1E includes a “PowerPrefIndication” field thatmay be set to a “lowpowerconsumption” state to indicate that the UE 100prefers a configuration that is primarily optimized for power savings.Otherwise, the UE 100 sets the PowerPrefIndication field to a “normal”state.

In one embodiment, a UE capable of providing power preferenceindications may initiate the procedure of communicating its powerpreference in several different situations including upon beingconfigured to provide power preference indications and upon change ofpower preference. Upon initiating the procedure, the UE 100 determineswhether it transmitted a power preference indication since it wasconfigured to provide power preference indications. If it did not, thenthe UE 100 initiates transmission of the UEAssistanceInformationmessage. If the UE 100 has already transmitted a power preferenceindication, it determines whether its current power preferenceinformation is different from the one indicated in the last transmissionof the UEAssistanceInformation message. If the current power preferenceis different, and a power preference indication timer has expired, theUE 100 initiates transmission of the UEAssistanceInformation messagewith the current information. Also, if the UE 100 had sent an updatedpower preference indication to a source cell just prior to handover,then after handover has completed the UE 100 initiates transmission ofthe UEAssistanceInformation message with the current information.

An example UEAssistanceInformation message structure including thePowerPrefIndication field is provided as:

-- ASN1START UEAssistanceInformation ::=   SEQUENCE { criticalExtensionsCHOICE {  c1   CHOICE{   ueAssistanceInformation-r11   UEAssistanceInformation-r11-IEs,   spare7 NULL,   spare6 NULL, spare5NULL, spare4 NULL,   spare3 NULL, spare2 NULL, spare1 NULL  }, criticalExtensionsFuture   SEQUENCE { } } }UEAssistanceInformation-r11-IEs ::=   SEQUENCE { powerPrefIndication-r11  PowerPrefIndication-r11  OPTIONAL, nonCriticalExtension SEQUENCE { } OPTIONAL } -- ASN1STOP

In response to the UE-AssistanceInfo IE 912, the eNodeB 114 may take oneor more actions or may decide to take no action. For example, the eNodeBmay respond by releasing the UE 100 (e.g., making it go into idle mode).As shown in FIG. 9, the eNodeB 114 may also respond to theUE-AssistanceInfo IE 912 by sending a drxSet-Config IE 914 to the UE 100with a request to change the DRX setting. The drxSet-Config IE 914 mayinclude a newly assigned DRX set or DRX set index. In one embodiment,the drxSet-Config IE 914 is an extension of theRadioResourceConfigDedicated IE. The MAC main configuration informationis transmitted from the eNodeB 114 to the UE 100 usingRadioResourceConfigDedicated. The RadioResourceConfigDedicated IE isused to setup, modify, and release radio bearers (RBs), to modify theMAC main configuration, to modify the semi-persistent scheduling (SPS)configuration, and to modify the dedicated physical configuration. Incertain embodiments, the RadioResourceConfigDedicated IE is modified toinclude a new element referred to herein as “drxSet-Config” IE that canalso be used to modify the DRX configuration.

FIG. 10 is a flow chart of a method 1000 for selecting or modifying aDRX set according to one embodiment. The method 1000 includes receiving1010 a radioResourceConfigDedicated message at the UE 100. Initially,the UE 100 queries 1012 whether the RRCConnectionReconfiguration messageincludes a fullConfig IE. If it does include a fullConfig IE, the UE 100performs the DRX sets update from the MAC-MainConfig IE. For eachdrxset-index value in the DRXSet (which is a list of DRX sets availableat the eNodeB 114), the UE 100 creates 1014 a DRX set and associates itwith the corresponding drxset-index. If the DRX set is alreadyconfigured corresponding to the received drx-index, the UE 100 modifies1016 the DRX set based on the current radioResourceConfigDedicatedDRXSet IE. The UE 100 then configures 1018 the current DRX set based onthe assigned-DrxSetIndex value.

The UE 100 may query 1020 whether the drxSet-Config 1E is present in theradioResourceConfigDedicated message When the fullConfig 1E is presentin the RRCConnectionReconfiguration message, theradioResourceConfigDedicated message usually does not include thedrxSet-Config IE. If the drxSet-Config 1E is present, however, the UE100 queries 1022 whether the drxset-index is present in the message. Ifthe drxset-index is present, the UE 100 reads 1024 the currentdrxset-index included in the drxSet-Config 1E and configures thecorresponding DRX set as the current DRX setting to use, until furtherchange. If, however the drxset-index is not present, the UE 100 gets1026 the Current-drxSet and configures the corresponding DRX set as theDRX setting to use, until further change.

If the the RRCConnectionReconfiguration message does not include afullConfig IE, then the UE 100 does not perform the DRX sets update fromthe MAC-MainConfig IE. Rather, after receiving a newradioResourceConfigDedicated message, the UE 100 queries 1022 whetherthe drxset-index is present in the message. If the drxset-index ispresent, the UE 100 reads 1024 the current drxset-index included in thedrxSet-Config 1E and configures the corresponding DRX set as the currentDRX setting to use, until further change. If, however the drxset-indexis not present, the UE 100 gets 1026 the Current-drxSet and configuresthe corresponding DRX set as the DRX setting to use, until furtherchange.

III. Example Mobile Device

FIG. 11 provides an example illustration of the mobile device that maybe used with one or more of the embodiments disclosed herein. The mobiledevice may be, for example, a UE, a mobile station (MS), a mobilewireless device, a mobile communication device, a tablet, a handset, orother type of mobile wireless device. The mobile device can include oneor more antennas configured to communicate with base station, such as aan eNodeB, a base band unit (BBU), a remote radio head (RRH), a remoteradio equipment (RRE), a relay station (RS), a radio equipment (RE), orother type of wireless wide area network (WWAN) access point. The mobiledevice can be configured to communicate using at least one wirelesscommunication standard including 3GPP LTE, WiMAX, High Speed PacketAccess (HSPA), Bluetooth, and WiFi. The mobile device can communicateusing separate antennas for each wireless communication standard orshared antennas for multiple wireless communication standards. Themobile device can communicate in a wireless local area network (WLAN), awireless personal area network (WPAN), and/or a WWAN.

FIG. 11 also provides an illustration of a microphone and one or morespeakers that can be used for audio input and output from the mobiledevice. The display screen may be a liquid crystal display (LCD) screen,or other type of display screen such as an organic light emitting diode(OLED) display. The display screen can be configured as a touch screen.The touch screen may use capacitive, resistive, or another type of touchscreen technology. An application processor and a graphics processor canbe coupled to internal memory to provide processing and displaycapabilities. A non-volatile memory port can also be used to providedata input/output options to a user. The non-volatile memory port mayalso be used to expand the memory capabilities of the mobile device. Akeyboard may be integrated with the mobile device or wirelesslyconnected to the mobile device to provide additional user input. Avirtual keyboard may also be provided using the touch screen.

Various techniques, or certain aspects or portions thereof, may take theform of program code (i.e., instructions) embodied in tangible media,such as floppy diskettes, CD-ROMs, hard drives, non-transitory computerreadable storage medium, or any other machine-readable storage mediumwherein, when the program code is loaded into and executed by a machine,such as a computer, the machine becomes an apparatus for practicing thevarious techniques. In the case of program code execution onprogrammable computers, the computing device may include a processor, astorage medium readable by the processor (including volatile andnon-volatile memory and/or storage elements), at least one input device,and at least one output device. The volatile and non-volatile memoryand/or storage elements may be a RAM, EPROM, flash drive, optical drive,magnetic hard drive, or other medium for storing electronic data. Thebase station and mobile station may also include a transceiver module, acounter module, a processing module, and/or a clock module or timermodule. One or more programs that may implement or utilize the varioustechniques described herein may use an application programming interface(API), reusable controls, and the like. Such programs may be implementedin a high level procedural or object oriented programming language tocommunicate with a computer system. However, the program(s) may beimplemented in assembly or machine language, if desired. In any case,the language may be a compiled or interpreted language, and combinedwith hardware implementations.

It should be understood that many of the functional units described inthis specification may be implements as one or more modules, which is aterm used to more particularly emphasize their implementationindependence. For example, a module may be implemented as a hardwarecircuit comprising custom VLSI circuits or gate arrays, off-the-shelfsemiconductors such as logic chips, transistors, or other discretecomponents. A module may also be implemented in programmable hardwaredevices such as field programmable gate arrays, programmable arraylogic, programmable logic devices or the like.

Modules may also be implemented in software for execution by varioustypes of processors. An identified module of executable code may, forinstance, comprise one or more physical or logical blocks of computerinstructions, which may, for instance, be organized as an object,procedure, or function. Nevertheless, the executables of an identifiedmodule need not be physically located together, but may comprisedisparate instructions stored in different locations which, when joinedlogically together, comprise the module and achieve the stated purposefor the module.

Indeed, a module of executable code may be a single instruction, or manyinstructions, and may even be distributed over several different codesegments, among different programs, and across several memory devices.Similarly, operational data may be identified and illustrated hereinwithin modules, and may be embodied in any suitable form and organizedwithin any suitable type of data structure. The operational data may becollected as a single data set, or may be distributed over differentlocations including over different storage devices, and may exist, atleast partially, merely as electronic signals on a system or network.The modules may be passive or active, including agents operable toperform desired functions.

Reference throughout this specification to “an example” means that aparticular feature, structure, or characteristic described in connectionwith the example is included in at least one embodiment of the presentinvention. Thus, appearances of the phrases “in an example” in variousplaces throughout this specification are not necessarily all referringto the same embodiment.

As used herein, a plurality of items, structural elements, compositionalelements, and/or materials may be presented in a common list forconvenience. However, these lists should be construed as though eachmember of the list is individually identified as a separate and uniquemember. Thus, no individual member of such list should be construed as ade facto equivalent of any other member of the same list solely based ontheir presentation in a common group without indications to thecontrary. In addition, various embodiments and example of the presentinvention may be referred to herein along with alternatives for thevarious components thereof. It is understood that such embodiments,examples, and alternatives are not to be construed as defactoequivalents of one another, but are to be considered as separate andautonomous representations of the present invention.

Although the foregoing has been described in some detail for purposes ofclarity, it will be apparent that certain changes and modifications maybe made without departing from the principles thereof. It should benoted that there are many alternative ways of implementing both theprocesses and apparatuses described herein. Accordingly, the presentembodiments are to be considered illustrative and not restrictive, andthe invention is not to be limited to the details given herein, but maybe modified within the scope and equivalents of the appended claims.

Those having skill in the art will appreciate that many changes may bemade to the details of the above-described embodiments without departingfrom the underlying principles of the invention. The scope of thepresent invention should, therefore, be determined only by the followingclaims.

The invention claimed is:
 1. A user equipment (UE), comprising: aninterface to send or receive a power preference indication parameter toor from a memory device; a processor to generate an uplink dedicatedcontrol channel (UL-DCCH) message in a third generation partnershipproject (3GPP) long term evolution (LTE) wireless network, wherein theUL-DCCH message comprises a power preference indication parameter toassist in a selection of a power saving setting; and a radio frequency(RF) transceiver to transmit the UL-DCCH message to an evolved node B(eNodeB) and to receive, in response, the power saving setting, whereinthe processor is further configured to determine that the RF transceivertransmitted the UL-DCCH message to a first cell of the wirelesscommunication network within a predetermined time period before ahandover of the UE from the first cell to a second cell of the wirelesscommunication network; and wherein in response to the determination andafter completion of the handover of the UE from the first cell to thesecond cell, the RF transceiver initiates transmission of the UL-DCCHmessage to the second cell.
 2. The UE of claim 1, wherein the processoris configured to selectively set the power preference indicationparameter between a normal power consumption setting and a low powerconsumption setting, wherein the low power consumption setting specifiesa request for the UE to enter into a power saving configuration.
 3. TheUE of claim 1, wherein the RF transceiver is further configured toreceive the power saving setting from the eNodeB as a discontinuousreception (DRX) setting.
 4. The UE of claim 1, wherein the UE isconfigured to connect to at least one of a wireless local area network(WLAN), a wireless personal area network (WPAN), and a wireless widearea network (WWAN), and the UE includes an antenna, a touch sensitivedisplay screen, a speaker, a microphone, a graphics processor, anapplication processor, internal memory, a non-volatile memory port, orcombinations thereof.